Open a Tag Heuer Aquaracer 300 case back

[LazyTimegrapher]

I mentioned this in my intro post but I’m wondering how to open the case back for the new tag heuer aquaracer 300. 
 

it’s a 300M dive watch, so I assumed a screw down case back. The crown is screw down. But the case back doesn’t have any indents to attach a tool to rotate the crown. 
 

another website said there are screws under the bezel, but I took the bezel off and there’s no screws on the bezel side.

 

any help would be appreciated 
 

you can see the case back in the link below

https://www.tagheuer.com/us/en/timepieces/engraving-online-service/43-mm-calibre-5-automatic/WBP208B.BF0631.html

[rjenkinsgb]

Try taking the strap off and see if there is a notch for a tool or knife in one of the strap recesses?

I've never seen one before but suspect it is a pry-off type, as it seems unlikely the text and logo would always be in perfect vertical alignment if it was a screw-on type?

 

[LazyTimegrapher]

I’ve taken the bracelet and bezel off and there’s no obvious way to take the case back off. Seems unlikely that a press on could be 300m water resistant, but the alignment of the logo and the lack of notches for an opening tool make it seem unlikely to be a standard screw down. 
 

I saw some threads mentioning “bayonet” and “cam lock” case backs for other watches, but it’s difficult to figure out if this watch uses those systems without being able to open it. The link below and the attached image mention the “cam lock” 

 

https://www.watchuseek.com/threads/aquaracer-300m-diver-with-snap-back-case.5299302/

the link below mentions screws on the bezel side, but I removed the bezel and there are no screws under the bezel so that information appears to be false.

 

http://tagheuerenthusiast.blogspot.com/2021/10/instructions-removing-backplate-of-2021.html?m=1

 

its not a cheap watch and was a gift from my wife, so I’m hesitant to be too rough with it especially if I don’t quite know what I’m doing.

 

ill remove the bezel and bracelet and post some pictures later today. 

[rjenkinsgb]

OK, the bayonet style fitting makes sense for alignment. Can you post photos with the bezel off?

 

[HectorLooi]

Maybe you could try a rubber ball or a suction grip opener.

https://www.cousinsuk.com/product/suction-grip-dies-with-holder-cousins

As a last resort, you could try the glued on nut trick.

[watchweasol]

Hi. Superglue and a nut then use a spanner to unscrew, acetone will dissolve the glue an clean up the back.

[Neverenoughwatches]

Is it possible that with the use of screwback case tool there is a special  socket that fits inside the internal facets. I'm not entirely sure why you are trying to remove the back, for whatever reason is it worth the risk of damaging the watch ?

Is it new ?

[RichardHarris123]

The removing the bezel and looking for screws going through to the back looks like the correct method.  Remove the bezel and post photos. 

http://tagheuerenthusiast.blogspot.com/2021/10/instructions-removing-backplate-of-2021.html?m=1

[Neverenoughwatches]

12 minutes ago, RichardHarris123 said:

The removing the bezel and looking for screws going through to the back looks like the correct method.  Remove the bezel and post photos. 

http://tagheuerenthusiast.blogspot.com/2021/10/instructions-removing-backplate-of-2021.html?m=1

I particularly liked that last sentence. 

In the link

I just wouldn't do it

[HectorLooi]

16 hours ago, LazyTimegrapher said:

another website said there are screws under the bezel, but I took the bezel off and there’s no screws on the bezel side.

In the original post, it seems there aren't any screws under the bezel.

[LazyTimegrapher]

I saw mention of the super glue and bolt method on various forums. I wondered if there’d be any problem with that given the watch is titanium. Will the glue or the acetone stain the metal? Titanium is supposed to be resistant to corrosion, but sometimes certain metals react with chemicals unexpectedly.

 

If it doesn’t stain or scratch the watch and can be completely removed with acetone, the bolt and glue method seems like a clever last resort approach.

 

However, I don’t think I’m ready to use that method on this watch. The watch is new, and it was a gift, and it wasn't cheap. Also, +10 spd really isn’t that big of a deal. I can just correct it once a week to keep it within a minute of the correct time. If I had a manual wind watch I’d have to wind it more often than every week, so I can think of it that way.

 

I think neverenoughwatches is right that this is the wrong watch to use to start learning how to repair watches. I think I’ll either buy the Unitas 6498 or a clone to do the watch fix course. I may also get a $200 invicata pro diver with the SW200 movement that I believe is also in the tag heuer aquaracer to start learning watch repair. It uses the “caliber 5” which I believe is just an SW200-1 or ETA 2824-2 with a tag decorated rotor.

 

How long would you all say it takes to develop basic competence working on mechanical watches? What level does one end up at after doing the first three watch fix courses?

 

I mentioned in my intro post that I was emboldened to try to regulate the tag watch by my success in swapping out a broken quartz movement on a friends 15 year old fashion watch a month or so ago. It had a Ronda 762 which was available new from Esslinger for $10. I didn’t have the right tools or any experience but I was able to remove the movement, swap the dial and hands, and reassemble the watch to fix it. It appears to work fine now. The only reason I attempted it though was because they were going to throw the watch out, so the risk was really just the $10 for the new movement. The risk on this aquaracer is much higher and probably above my risk threshold.

 

Also thanks very much for all your suggestions and help. I’ll post some more images of the watch shortly.

[Neverenoughwatches]

17 minutes ago, LazyTimegrapher said:

I saw mention of the super glue and bolt method on various forums. I wondered if there’d be any problem with that given the watch is titanium. Will the glue or the acetone stain the metal? Titanium is supposed to be resistant to corrosion, but sometimes certain metals react with chemicals unexpectedly.

 

If it doesn’t stain or scratch the watch and can be completely removed with acetone, the bolt and glue method seems like a clever last resort approach.

 

However, I don’t think I’m ready to use that method on this watch. The watch is new, and it was a gift, and it wasn't cheap. Also, +10 spd really isn’t that big of a deal. I can just correct it once a week to keep it within a minute of the correct time. If I had a manual wind watch I’d have to wind it more often than every week, so I can think of it that way.

 

I think neverenoughwatches is right that this is the wrong watch to use to start learning how to repair watches. I think I’ll either buy the Unitas 6498 or a clone to do the watch fix course. I may also get a $200 invicata pro diver with the SW200 movement that I believe is also in the tag heuer aquaracer to start learning watch repair. It uses the “caliber 5” which I believe is just an SW200-1 or ETA 2824-2 with a tag decorated rotor.

 

How long would you all say it takes to develop basic competence working on mechanical watches? What level does one end up at after doing the first three watch fix courses?

 

I mentioned in my intro post that I was emboldened to try to regulate the tag watch by my success in swapping out a broken quartz movement on a friends 15 year old fashion watch a month or so ago. It had a Ronda 762 which was available new from Esslinger for $10. I didn’t have the right tools or any experience but I was able to remove the movement, swap the dial and hands, and reassemble the watch to fix it. It appears to work fine now. The only reason I attempted it though was because they were going to throw the watch out, so the risk was really just the $10 for the new movement. The risk on this aquaracer is much higher and probably above my risk threshold.

 

Also thanks very much for all your suggestions and help. I’ll post some more images of the watch shortly.

I think you are making the right decision here, it is far too valuable and not worth the risk for improving its performance  by just a few seconds, which might not even be that easy to achieve and it could go very wrong. So just 2 things to add to convince you to leave it well alone 1. If the watch is brand new and you take the back off, you can definitely kiss your guarantee goodbye and 2. 10 seconds incorrect rate on a timegrapher ( we didn't discuss the amplitude,  wind or positional variations )  doesn't mean 10 seconds incorrect rate on your wrist and on your bedside table, it could very well be more accurate than that. 

[RichardHarris123]

Have you got photos with the bezel off, I  totally agree about not spoiling such a watch but I would like to know how the back is removed. 

[LazyTimegrapher]

Attached are images of the watch from various angles. I’m still interested in unraveling the mystery of how the case back is opened, although I probably won’t attempt it any time soon.

 

The little bent metal under the bezel is I believe part of the mechanism for the unidirectional winding bezel. Perhaps that can be pulled off somehow to reveal screws below, but it’s hard for me to imagine that removing that metal ring is the way to open the watch. That metal ring doesn’t look like it’s meant to be removed in a regular service.

 

the other images show that there are gaps between the case back and the case. I do suspect it needs to be rotated to come off, but I’m not adventurous enough to attempt trail an error on this watch.

[RichardHarris123]

I really don't want to be responsible for any damage to the watch but the screws could be under the bezel spring. 

[LazyTimegrapher]

How does one go about removing that metal plate? Has anyone removed that on a dive watch before?

[LazyTimegrapher]

2 hours ago, Neverenoughwatches said:

I think you are making the right decision here, it is far too valuable and not worth the risk for improving its performance  by just a few seconds, which might not even be that easy to achieve and it could go very wrong. So just 2 things to add to convince you to leave it well alone 1. If the watch is brand new and you take the back off, you can definitely kiss your guarantee goodbye and 2. 10 seconds incorrect rate on a timegrapher ( we didn't discuss the amplitude,  wind or positional variations )  doesn't mean 10 seconds incorrect rate on your wrist and on your bedside table, it could very well be more accurate than that. 

You’ve persuaded me that it’s not worth risking it with this watch just yet. However, I am still curious how to open it.

 

regarding the daily rate, the +10spd is measured on my wrist. Every 24hours I wear it, it gains about 10 seconds, and it gains about 70 seconds in 7 days. So the +10spd is the average daily rate when I wear it 24hrs/day. 

 

on the time grapher the rates are all over the place.  Amplitude is around 290-300 in all positions.
Dial up it’s +10spd

3 down it’s +18spd

12 down it’s +5spd

6 down it’s +20spd

dial down its +13spd

9 down it’s +4spd

 

I guess this means my wearing habits are mostly dial up. Perhaps also including  equal amounts of 3 down and 12 down which cancel each other out.

 

Since everything is biased fast, I thought I could slow it down to have it get closer to 0spd on dial up with some slow and fast in the other positions.

[LazyTimegrapher]

As far as my watch repairing plans go, I think I’ll buy some cheaper watches and/or watch movements to practice on. Probably the recommended ETA 6498 for the course and an SW200-1 / Invicta diver for practicing on a watch similar to the aquaracer.

 

Given the daily rates for the aquaracer, I suspect it has a standard/base grade of the SW200-1. My long term plan is to buy a top grade SW200-1 movement from Switzerland with the better balance and hairspring and swap that movement into the aquaracer to improve the timekeeping. A movement swap for a nice mechanical probably isn't trivial though, so that’s probably a plan for down the road when the watch needs servicing or when I feel confident enough that I can do the job without destroying the watch.

 

however, if anyone has ideas for how this watch opens I’m interested to hear them.

[rjenkinsgb]

There is visibly a circular plate spring where the bezel fits, that appears to just lift out once the bezel is off?

It looks like there are holes or recesses under that, which may contain the supposed screws???

 

Edited June 17, 2024 by rjenkinsgb
typo

[Neverenoughwatches]

1 hour ago, LazyTimegrapher said:

You’ve persuaded me that it’s not worth risking it with this watch just yet. However, I am still curious how to open it.

 

regarding the daily rate, the +10spd is measured on my wrist. Every 24hours I wear it, it gains about 10 seconds, and it gains about 70 seconds in 7 days. So the +10spd is the average daily rate when I wear it 24hrs/day. 

 

on the time grapher the rates are all over the place.  Amplitude is around 290-300 in all positions.
Dial up it’s +10spd

3 down it’s +18spd

12 down it’s +5spd

6 down it’s +20spd

dial down its +13spd

9 down it’s +4spd

 

I guess this means my wearing habits are mostly dial up. Perhaps also including  equal amounts of 3 down and 12 down which cancel each other out.

 

Since everything is biased fast, I thought I could slow it down to have it get closer to 0spd on dial up with some slow and fast in the other positions.

Curiosity is how we learn from wanting to know things. If you want to get inside it at least wait until the warranty has expired. I expected the rates to be better , did you say a Sellita ? do we know what the specified are ?

[RichardHarris123]

We do.

[Neverenoughwatches]

1 minute ago, RichardHarris123 said:

We do.

Thats the end of that then, not something we can argue with.

[VWatchie]

11 hours ago, Neverenoughwatches said:

I'm not entirely sure why you are trying to remove the back

As repairers and enthusiasts, we always want to see the movement or we simply want to figure it out well in advance of the inevitable service that will happen sometime in the future! 

6 hours ago, LazyTimegrapher said:

It uses the “caliber 5” which I believe is just an SW200-1 or ETA 2824-2 with a tag decorated rotor.

We often forget that Sellita's (and ETA's) movements are made in different grades. In an Invicta we can count on their simplest grade, and in Caliber 5 their finest, so your numbers have me a bit puzzled, within spec though. Most important is that it gains or loses roughly the same number of seconds per day.

I always get a little concerned when I read comments that disdain and dismiss watches like Tag Heuer's Aquaracer with "the fact that it only has a simple movement from Sellita" when in fact it has a movement of fantastic quality.

6 hours ago, LazyTimegrapher said:

What level does one end up at after doing the first three watch fix courses?

Well, I felt like a Master Watchmaker and owner of the world! Seriously! Then after six months or so I slowly started to realize I had only scratched the surface. After another six months, I knew for sure I had only scratched the surface. Nevertheless, working on watches is a wonderful way to waste your time! 

Edited June 17, 2024 by VWatchie

[Neverenoughwatches]

34 minutes ago, VWatchie said:

Most important is that it gains or loses roughly the same number of seconds per day.

Known as precise but not accurate , hitting the same mark each day just not the accuracy mark.

[LazyTimegrapher]

1 hour ago, VWatchie said:

We often forget that Sellita's (and ETA's) movements are made in different grades. In an Invicta we can count on their simplest grade, and in Caliber 5 their finest, so your numbers have me a bit puzzled, within spec though. Most important is that it gains or loses roughly the same number of seconds per day.

I always get a little concerned when I read comments that disdain and dismiss watches like Tag Heuer's Aquaracer with "the fact that it only has a simple movement from Sellita" when in fact it has a movement of fantastic quality.

I really like the Tag Heuer aquaracer, particularly the model that my wife got for me. It was a watch I had wanted for quite some time. I know that online and on some forums people like to trash the brand for whatever reason, but the adjustable bracelet and the general look and feel of the watch are just great. It’s very lightweight and very comfortable due to the design and the titanium material. I also think it looks great.
 

I also don’t understand why many look down on ETA and Sellita. They are movement manufacturers and make great or at least good movements. 
 

The only thing that surprised me is that Tag used the lowest grade of movement for such a nice watch. I would have expected a higher grade given the price and also the quality of the rest of the watch.
 

However, it hasn’t soured me on the watch at all. On the contrary, it’s given me the challenge of swapping in a top grade movement once I feel capable of such a task.  
 

I'm not sure  where I read it, but I do believe I read that they used the lowest grade. I could be wrong though, so if anyone finds better information on the movement, let me know. On their website all they say is that it’s a “caliber 5”, which provides hardly any information at all.
 

I also aspire eventually to create a custom sapphire case back to put on the watch, but that will be more challenging given that it will need to be custom manufactured somehow.

I don’t ever plan to sell or give up the watch, so resale value doesn’t matter to me. I just look forward to one day turning this watch into the finest version of itself, at least according to my own tastes.

 

Perhaps I’ll even add my own custom finishing or engraving to the movement to view through the see through case back.

 

Whether or not any of this is feasible is another question, but it seems like a fun goal to pursue during my lifetime. It’ll give me a fun reason to learn watchmaking  at the very least.